According to a new study published in the journal Neurolmage, short bouts of aerobic exercise (such as HIIT training) can prevent our brains from shrinking and protect against cognitive decline.

Lead researcher Joseph Firth puts this down to a chemical called BDNF, which is released when we exert ourselves. He explains that this causes the hippocampus – the part of the brain that is associated with memory, emotions and motivation – to grow in volume in response.

“[The reason the brain declines] is partly due to less BDNF in the brain,” Firth explains.